This invention relates to packaging materials generally, and is more specifically related to reels or spools for packaging.
Reel packages and spool packages are used for the packaging of products which are produced in a continuous and connected manner and are packaged in large number or high count continuous lengths for long run use, including automated use. These products are typically packaged in a xe2x80x9cribbon woundxe2x80x9d (layer on layer) or convolute manner on a central core of a size closely matching the width of the manufactured product, so that the user of the product may unwind the product in an orderly, controlled manner for use or installation in other products. Products which are packaged on reels and spools are made of a wide variety of raw materials including metals, plastics, textiles and other products. The stiffness of some continuous products is such that the package must have a core with a large circumference (12 to 20xe2x80x3) to prevent undesired curling or bending of the manufactured product. Additionally, packages for these products have sidewalls or flanges which act as retainers to keep the product from slipping off and becoming twisted, bent, damaged or difficult or impossible to use. The sidewalls for larger reels used for relatively rigid products range in size from 20xe2x80x3 to 48xe2x80x3, and are made of corrugated board, solid fibreboard, Masonite, plastic and plywood. While there are technical differences between spools and reels as these terms are used in the art, the term xe2x80x9creelxe2x80x9d is used herein to indicate reels and spools used for packaging.
The cores of prior art reels are made of a number of substrates such as pre-formed and pre-cut styrofoam discs, or pressed wood, or plywood discs. Another embodiment employs rings of paper tubing cut from pre-made large diameter spiral or convolute paper tubes of a size or width which very nearly matches the width of the product being packaged. The sidewalls or flanges are then attached or fastened in a manner which protects the product from external damage, confines the product to minimal sidewise movement, and keeps the product wound in a single width convolute package, thereby allowing for orderly unwinding of the product by the user.
The methods employed in the prior art for joining sidewalls or flanges to cores are varied. Since some of the cores are discs with solid sides (such as styrofoam or pressed wood), adhesives are applied to these sides and the sidewalls of paper and corrugated board are brought into contact and unitized by the curing of the adhesive.
Other packages are of such large diameter that factors such as weight and cost make solid cores impractical. In such cases, cores are formed of paper rings of appropriate diameter and face width (matching the product to be wound) which are centered on sidewalls with holes punched to accept flat head threaded bolts of a length appropriate to the width of the product (with allowance for the thickness of the sidewall substrates). The bolt holes are positioned in close proximity to the rings, so that when they are tightened, they eliminate, or minimize, rotation of the ring. The second sidewall is positioned, and bolts are pressed through both sidewalls, and capped head or xe2x80x9cTxe2x80x9d nuts are attached to the bolts and tightened, creating a circular package or reel customized to the products width and load area. The load area is the area from the ring or core to the outside diameter of the flange or sidewall is the load area.
The sidewalls or flanges often have punches or apertures for different functions positioned on its face such as:
1. A center or arbor hole for mounting on an axis or rod for smooth xe2x80x9ctake upxe2x80x9d or xe2x80x9clet offxe2x80x9d of the continuous product.
2. A drive hole to accept a pin which will, when a rotational force is applied, turn the package and thereby wind or xe2x80x9ctake upxe2x80x9d the product as it is produced. (This arbor and drive hole configuration has become largely standardized and has a fixed central location)
3. Small apertures for inspection, product access and handling, which have no meaningful structural significance.
The present invention is an improvement of reel or spool packages. The package of the present invention comprises opposing sidewalls or flanges formed of the specified or appropriate substrate which are connected by a core. The core is formed by a partition which acts as a mold, such as a simplified paper ring, filled with a flowable material which hardens. The flowable material may be a two part expandable polyurethane foam which is applied into the partition by a metering and injection device. The chemistry of the foam formulation may be altered to change density, rigidity and flexibility as required by package stresses. The foam is a very aggressive and effective adhesive medium, which forms the core while connecting the sidewalls to form the package.